Conventional portable two-way radios usually have an antenna port to which an antenna is removably coupled. If an incorrect or damaged antenna is coupled to the port then undesirable relatively large standing waves will result. These standing waves are due to mismatch between the antenna and power amplifier circuitry inside the two-way radio. Unfortunately, these standing waves affect the performance of the radio and can cause damage to the amplifier circuitry. Accordingly, upon detection of mismatch, conventional radios will reduce the amplifier circuitry's output power to decrease current drain. However, this can still cause damage to the amplifier circuitry especially if unduly large standing waves are created by mismatch.